I have a Samsung NP-QX411. It has two graphics cards, Intel and nVidia. The Intel drivers were quickly found and is fully functional. But nVidia, I have tried installing several drivers in different ways. But I can not run it without success. I do not understand how Ubuntu has by default the switch Hybrid Graphics option. What should I do?

Bumblebee aims to provide support for NVIDIA Optimus laptops for GNU/Linux distributions. Using Bumblebee, you can use your NVIDIA card for rendering graphics which will be displayed using the Intel card.

Your nVidia card is not functioning as a GPU but it surely is ON all the time you are on Ubuntu ( hence, the battery life shown would be half of what it should have been). All the steps can be found here . Please make sure you follow the instructions corresponding to your current Ubuntu version.

Once you have Bumblebee up and running, your nVidia card would ALWAYS be off until you use the optirun command. Consult the Bumblebee wiki at all times.

This answers your question of switching between the cards.
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